Alarm-lock.



G. PESENBEL ALARM LOCK. APPLICATION FILED OOI.'6, 180B.

1 Patented Feb. 16, 1909.

511mm for arfesiselzdel Witnmu w M a UNITED strarns CHARLES FESENB EK, OF PHILADELPHIA, PENISYLVA PATENI OFFllQlzl.

TO FREDERICK FESENBEK' AND ONE-FOURTH '10 JOHN GRIMM, BOTH OF PHILADEL- PHIA, PENNSYLVANIA.

ALARM-LOOK.

To all whom it may concern:

Be it known t: at 1, CHARLES FESENBEK, a citizen of the United States, residing at Philadelpiia, in the county of Philadelphia and tate of Pennsylvania, ii ave invented certain new and useful Improvements in Alarm- Locks, of which the following is a specifica tion.

My invention relates to improvements in alarm locks, and more particularly to an im proved attachment wiich may be employed on any well known form of lock to close an electric circuit and sound an alarm, when the sliding bolt is moved toward its unlocking position.

A further object is to provide an extremely simple and inexpensive construction which may be attached to a lock at small cost which is not'liabletoget out of order, u i 'it h uld, anbe asily p i d A further object is to provide improve ments of this character in which the electric circuit will be closed as soon as the sliding bolt begins its unlocking movement, and will be maintained closed to constantly sound the alarm until the bolt is again moved to its full locking position.

A further object is to provide improvements of this character with an improved mounting for the movable contact and so construct the mounting or support as to prevent any possibility of the contact being tampered with, by an instrument inserted through the keyhole of the lock.

lVith these and other objects in view the invention consists in certain novel features of construction, combinations and arrangements of parts as will be more fully hereinafter described and set forth in the claims.

In the accompanying drawings Figure 1, is a view in elevation of a portion of an ordinary lock, with a side plate removed, illustrating my improved attachment in place, with the bolt in its locking position. Fig. 2, is a view in horizontal section through the lock casing illustrating my improvements in top plan. Fig. 3, is a top plan view of the insulating block or support, and Fig. 1, is a detached pers ective view of the contact secured to the sliding bolt.

1 represents a lock casing, in which a sliding bolt 2 is mounted, and held in locked and unlocked osition by an ordinary tumbler 3 until the latter is moved by tne key, not shown, as is common in all looks of this char- Specification of Letters Patent.

Application filed. Dctober 6, 1908.

Patented Feb. 16, 1909.

Serial No. 456,492.

4 acter. 4 represents a block, preferably of rubber, or other insulating material, secured by a screw 5 and nut 6, to the casing wall, and made with projections or enlargements '7 at each end, located in openingsinthe casing wall to receive binding posts 8 and 9 res sectively, and insulate the latter from the lock casing. the keyhole 10 in the lock casing, is provided with an extension or shield 11, which prevents any tampering with the contact mech anism by an instrument inserted through the keyhole.

A contact piece 12, preferably in the form of an angle bracket, as shown in Fig. 4, is secured to the sliding bolt 2, and provided on its inner face with a notch 13, in which a circuit wire; 14,15 clamped. against the sliding nectedin anelectric circuitwith a switch 155, battery'lfi, and bell 17 the other terminal of said circuit being the binding post 9.

A contact arm 18 is pivotally secured to the inner end of binding post 9 and is provided with a shoulder 19 to engage a stop 20 on block 4 and limit the movement of the arm toward the contact piece 12, on bolt 2. A spring 21 pressing against the arm 18 normally holds the latter with its shoulder 19 against stop 20, and is adapted to return the arm to this position when permitted by the movement of the bolt. It will be observed as shown in Fig. 1, that when the bolt is in its full locking position, the arm 18 and contact 12 are spaced a short distance apart and the electric circuit is therefore open.

The switch 15 may of course be located in any convenient part of the house, and during the day, is opened, so that the manipulation of the bolt 2 will not sound the alarm. At night the switch is turned to close the circuit, and should the bolt 2 then be moved inward, even though very slightly, the circuit will be closed by the contact piece 12 and arm 18 and the alarm sounded, and by the arrangement of the pivotal arm and spring, the electric contact will be maintained during the entire unlocking of the bolt, and also during the locking movement thereof, until the bolt is moved to its full locked position. It will therefore be seen that it will be impossible to unlock a door having my improved alarm attachment on its look without sounding an NIA, ASSIGNOR- OF THREE-FOURTHS' This block 4 at one end, adjacent to,

boltwhen-th e ,contactpiece is secured to the; s wire 14, recon-j: nestedto lnd ng-p stfiandti a atte' 13 alarm to rouse the house, and hence my improvements are an efi'ectual safe guard against burglars.

While 1 have shown and described what I believe to be a preferred form of my invention, I am aware that slight changes might bemade, and hence i do not restrict myself to the precise details set forth, but consider myself "at liberty to make such changes and alterations as fairly fall within the spirit and scope of my invention.

having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. In an electric alarm for locks, the combination with a lock casing and a sliding bolt in said casing, of a block of insulating material secured in said casing, pro ections on said block extending through openings in the casing, binding posts supported in said block, a contact arm in the casing pivoted to one of said binding posts, a contact piece on the bolt, a wire connecting the other post with said contact piece, a spring pressing the arm toward the contact piece on the bolt, and a stop limiting the movement of the arm in that direction.

2. in an electric alarm for looks, the combination with a casing and a sliding bolt therein, of a block of insulating material in said casing, projections on said block located in openings in the wall of said casing, binding posts secured in said block passing through the same, and located in the projections insulating them from the lock casing, a contact arm pivoted on one of said binding posts, a

stop on the-block limiting the movement of the arm in one direction, a sprin pressing the arm against said stop, a contact piece on the bolt, a wire connecting the contact piece with the other binding post, said contact piece and arm being spaced apart only when the bolt is in full locking position, and an electric battery, bell and switch connected in an electric circuit with said binding posts.

3. in an electric alarm for locks, the combination with a casing and a sliding bolt therein, of a block of insulating material in said casing, projections on said block located in openings in the wall of said casing, binding posts secured in said projections and extending through the block, a contact arm pivoted on one of said binding posts, a burglar shield or guard on one end of said block between the contact arm and the keyhole of the casing, a stop on the block limiting the movement of the arm in one direction, a spring pressing the arm against said stop, a contact piece on the bolt, a vidre connecting the contact piece with the other binding post, said contact piece and arm being spaced apart only when the bolt is in full locking position, and an electric battery, bell and switch connected in an electric circuit with said binding posts.

in testimony whereof i have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES FESENBEK.

Witnesses R. H. KRENKEL, J. A. L. MULHALL. 

